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Crowley, John

Publications and source records attributed to Crowley, John.

Thermocouple assembly

Disclosed is a thermocouple assembly having a resilient mount; a buffer having a first side and a second side, with the buffer first side connecting with the resilient mount; an insulator having a first side and a second side, with the insulator first side connecting with the buffer second side; and a thermocouple having a first side and a second side, the thermocouple first side connecting with the insulator second side, and the thermocouple second side being configured to be in thermal contact with an object to be measured.

Schwarting, Nelson↗

Visual Vestibular Interaction in the Dynamic Visual Acuity Test during Voluntary Head Rotation

Although intact vestibular function is essential in maintaining spatial orientation, no good screening tests of vestibular function are available to the aviation community. High frequency voluntary head rotation was selected as a vestibular stimulus to isolate the vestibulo-ocular reflex (VOR) from visual influence. A dynamic visual acuity test that incorporates voluntary head rotation was evaluated as a potential vestibular function screening tool. Twenty-seven normal subjects performed voluntary sinusoidal head rotation at frequencies from 0.7-4.0 Hz under three different visual conditions: visually-enhanced VOR, normal VOR, and visually suppressed VOR. Standardized Baily-Lovie chart letters were presented on a computer monitor in front of the subject, who then was asked to read the letters while rotating his head horizontally. The electro-oculogram and dynamic visual acuity score were recorded and analyzed. There were no significant differences in gain or phase shift among three visual conditions in the frequency range of 2.8 to 4.0 Hz. The dynamic visual acuity score shifted less than 0.3 logMAR at frequencies under 2.0 Hz. The dynamic visual acuity test at frequencies a round 2.0 Hz can be recommended for evaluating vestibular function.

VISUAL ACUITY↗